Separation of p-cresol from the cresol isomers by stripping crystallization

Stripping crystallization (SC) is a new separation technique, which combines distillation and crystallization. In the previous research, SC has been successfully applied to separate p-xylene from the mixed xylenes by Shiau et al. The application of SC to separate the p-cresol/m-cresol mixture was studied. Due to the close boiling points, it was very difficult to separate them by conventional distillation. The SC experiments showed that p-cresol could be purified from 90 to 96%+, from 95 to 98%+, from 97% to 98%+ , or from 98% to 99%+ in the p-cresol-enriched mixture. The experimental results were consistent with the simulation results. The recovery rate of p-cresol in the experiments could be greatly improved by adjusting the operating temperature and pressure during the SC process. This is an abstract of a paper presented at the AIChE Spring National Meeting and 5th Global Congress on Process Safety (Tampa, FL 4/26-30/2009).